Re: [PATCH] term/serial: Add support for PCI serial devices

[Peter Zijlstra <peterz@infradead.org>]

How's this then? seems to build. If this looks allright, I'll post it as
v2 I suppose.

---
diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def
index 5212dfab1369..c0683da2353b 100644
--- a/grub-core/Makefile.core.def
+++ b/grub-core/Makefile.core.def
@@ -224,12 +224,14 @@ kernel = {
 
   i386_efi = kern/i386/efi/init.c;
   i386_efi = bus/pci.c;
+  i386_efi_cppflags = '-DGRUB_HAS_PCI';
 
   x86_64 = kern/x86_64/dl.c;
   x86_64_xen = kern/x86_64/dl.c;
   x86_64_efi = kern/x86_64/efi/callwrap.S;
   x86_64_efi = kern/i386/efi/init.c;
   x86_64_efi = bus/pci.c;
+  x86_64_efi_cppflags = '-DGRUB_HAS_PCI';
 
   xen = kern/i386/tsc.c;
   xen = kern/i386/xen/tsc.c;
@@ -271,6 +273,7 @@ kernel = {
   i386_pc = term/i386/pc/console.c;
 
   i386_qemu = bus/pci.c;
+  i386_qemu_cppflags = '-DGRUB_HAS_PCI';
   i386_qemu = kern/vga_init.c;
   i386_qemu = kern/i386/qemu/mmap.c;
 
@@ -303,6 +306,7 @@ kernel = {
   mips_loongson = bus/bonito.c;
   mips_loongson = bus/cs5536.c;
   mips_loongson = bus/pci.c;
+  mips_loongson_cppflags = '-DGRUB_HAS_PCI';
   mips_loongson = kern/mips/loongson/init.c;
   mips_loongson = term/at_keyboard.c;
   mips_loongson = term/ps2.c;
@@ -2047,6 +2051,8 @@ module = {
   ieee1275 = term/ieee1275/serial.c;
   mips_arc = term/arc/serial.c;
   efi = term/efi/serial.c;
+  x86 = term/pci/serial.c;
+  mips_loongson = term/pci/serial.c;
 
   enable = terminfomodule;
   enable = ieee1275;
diff --git a/grub-core/term/pci/serial.c b/grub-core/term/pci/serial.c
new file mode 100644
index 000000000000..581d0760f9f4
--- /dev/null
+++ b/grub-core/term/pci/serial.c
@@ -0,0 +1,83 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2000,2001,2002,2003,2004,2005,2007,2008,2009,2010  Free Software Foundation, Inc.
+ *
+ *  GRUB is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/serial.h>
+#include <grub/term.h>
+#include <grub/types.h>
+#include <grub/pci.h>
+#include <grub/mm.h>
+#include <grub/misc.h>
+
+static int
+find_pciserial (grub_pci_device_t dev, grub_pci_id_t pciid, void *data)
+{
+  grub_pci_address_t cmd_addr, class_addr, bar_addr;
+  struct grub_serial_port *port;
+  grub_uint32_t class, bar;
+  grub_uint16_t cmdreg;
+  int *nr = data;
+  int err;
+
+  (void)pciid;
+
+  cmd_addr = grub_pci_make_address (dev, GRUB_PCI_REG_COMMAND);
+  cmdreg = grub_pci_read (cmd_addr);
+
+  class_addr = grub_pci_make_address (dev, GRUB_PCI_REG_REVISION);
+  class = grub_pci_read (class_addr);
+
+  bar_addr = grub_pci_make_address (dev, GRUB_PCI_REG_ADDRESS_REG0);
+  bar = grub_pci_read (bar_addr);
+
+  /* 16550 compattible MODEM or SERIAL */
+  if (((class >> 16) != GRUB_PCI_CLASS_COMMUNICATION_MODEM &&
+       (class >> 16) != GRUB_PCI_CLASS_COMMUNICATION_SERIAL) ||
+      ((class >> 8) & 0xff) != GRUB_PCI_SERIAL_16550_COMPATIBLE)
+    return 0;
+
+  if ((bar & GRUB_PCI_ADDR_SPACE_MASK) != GRUB_PCI_ADDR_SPACE_IO)
+    return 0;
+
+  port = grub_zalloc (sizeof (*port));
+  if (!port)
+    return 0;
+
+  grub_pci_write (cmd_addr, cmdreg | GRUB_PCI_COMMAND_IO_ENABLED);
+
+  port->name = grub_xasprintf ("pci%d", (*nr)++);
+  port->driver = &grub_ns8250_driver;
+  port->port = bar & GRUB_PCI_ADDR_IO_MASK;
+  err = grub_serial_config_defaults (port);
+  if (err)
+    {
+      grub_print_error ();
+      return 0;
+    }
+
+  grub_serial_register (port);
+
+  return 0;
+}
+
+void
+grub_pciserial_init (void)
+{
+  int nr = 0;
+
+  grub_pci_iterate (find_pciserial, &nr);
+}
diff --git a/grub-core/term/serial.c b/grub-core/term/serial.c
index 842322b1c607..09c9e1cd1fdc 100644
--- a/grub-core/term/serial.c
+++ b/grub-core/term/serial.c
@@ -448,6 +448,9 @@ GRUB_MOD_INIT(serial)
 #ifdef GRUB_MACHINE_ARC
   grub_arcserial_init ();
 #endif
+#ifdef GRUB_HAS_PCI
+  grub_pciserial_init ();
+#endif
 }
 
 GRUB_MOD_FINI(serial)
diff --git a/include/grub/pci.h b/include/grub/pci.h
index 262c89b748bb..b228bb1b71fd 100644
--- a/include/grub/pci.h
+++ b/include/grub/pci.h
@@ -80,8 +80,13 @@
 
 #define  GRUB_PCI_STATUS_DEVSEL_TIMING_SHIFT 9
 #define  GRUB_PCI_STATUS_DEVSEL_TIMING_MASK 0x0600
+
 #define  GRUB_PCI_CLASS_SUBCLASS_VGA  0x0300
 #define  GRUB_PCI_CLASS_SUBCLASS_USB  0x0c03
+#define  GRUB_PCI_CLASS_COMMUNICATION_SERIAL  0x0700
+#define  GRUB_PCI_CLASS_COMMUNICATION_MODEM   0x0703
+
+#define  GRUB_PCI_SERIAL_16550_COMPATIBLE 0x02
 
 #ifndef ASM_FILE
 
diff --git a/include/grub/serial.h b/include/grub/serial.h
index 67379de45dd1..c57aed19ff2b 100644
--- a/include/grub/serial.h
+++ b/include/grub/serial.h
@@ -193,6 +193,8 @@ const char *
 grub_arcserial_add_port (const char *path);
 #endif
 
+void grub_pciserial_init (void);
+
 struct grub_serial_port *grub_serial_find (const char *name);
 extern struct grub_serial_driver grub_ns8250_driver;
 void EXPORT_FUNC(grub_serial_unregister_driver) (struct grub_serial_driver *driver);